drivers/char/xillybus

Xillybus FPGA-to-host interface IP cores (PCIe, DT, and USB)

Host-side support for Xillybus, a commercial FPGA IP core that lets a custom FPGA design expose simple data pipes to a Linux host over PCIe, on-chip buses described in the device tree (such as Zynq AXI), or USB via the XillyUSB variant. It is mainly used by engineers building custom FPGA-based instruments, accelerators, and industrial appliances.

keep-annotate conf=0.82 last_sold=2025 deploy=low replacement=none subsystem=char category=bus-other
82%

recommendation

Worth keeping but documenting its niche because the hardware is a commercial FPGA-to-host IP-core product still sold and updated by Xillybus Ltd. in 2025, with the kernel code seeing fresh maintenance commits as recently as November 2025. There is no substitute in-tree driver for this vendor's IP stack, so removal would strand the small but active community of FPGA designers and lab or industrial appliance builders who rely on it.

repository signals

9 files
4,916 source lines
26 commits, 5y
+2,809 / −518 lines added / removed, 5y
15 authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 26 total · active in 18/61 months
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sources

  1. lore.kernel.org

    Recent upstream maintenance touched this driver in 2025, indicating it is not abandoned.

  2. xillybus.com

    Vendor still markets Xillybus/XillyUSB as current FPGA-to-host products for PCIe, AXI, and USB, with Linux support.

  3. xillybus.com

    Vendor still publishes current PCIe demo bundles targeting modern FPGA boards such as UltraScale+, Versal, and Zynq platforms.

  4. xillybus.com

    Vendor still offers the XillyUSB variant and states an adapter kit is available for purchase.

codex reasoning notes (technical)

Local source inspection (`rg`, `sed`) shows real driver code for PCIe, OF/DT, and USB-backed Xillybus endpoints. lore_file_timeline on `drivers/char/xillybus/xillyusb.c` returned active hits through 2025-11-07 (obtained via MCP), so this is still seeing upstream maintenance rather than removal. Official vendor pages were obtained via web search on `xillybus.com`; they show the product line is still sold/marketed for new FPGA designs in 2025, but the use case is niche: custom FPGA systems, dev boards, lab/industrial appliances, not mass consumer hardware. There is no obvious in-tree replacement driver for the same vendor-specific FPGA IP-core stack, so removal would strand active though specialized users; annotate rather than deprecate.